The SunFun started as a foot-launched glider design, the VJ-24, and was developed into a wheeled undercarriage motor glider, the VJ-24W. The VJ-24 was derived from the earlier Volmer VJ-23 Swingwing and differed from that design by replacing the wooden structure with metal and employing a constant chord, strut-braced wing in place of the VJ-23's cantilever, tapered wing.
The aircraft is built from aluminium tubing covered with aircraft fabric. The 36.51NaN1 span wing is braced by V-struts, supported by triangular jury struts. The fuselage is built around a keel tube that mounts the cruciform tail at the aft end, the wing and cockpit in the center and the engine at the front. The specified engines are the Yamaha KT100 150NaN0 go-kart powerplant and the 100NaN0 McCulloch MAC-101, mounted in tractor configuration on the front of the keel tube, above the aircraft's nose. The landing gear is of conventional configuration, using spoked bicycle wheels for the main gear. Pilot weight is limited to 2000NaN0.
The take-off and landing distances with the 150NaN0 engine are both 1000NaN0.
In 1998 plans cost US$100 and the estimated cost of the materials to build the VJ-24W were US$2400. The estimated construction time is 250 hours.
